Copyright © 2012 Open Geospatial Consortium.
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urn:misb:def:eg0903:TargetIntensity Unused – for
Infrared Systems
N Target Intensity
urn:misb:def:eg0903:TargetPriority NA
N Target Priority
One observed property that should have been included in the target offering was the frame number. Because the frame number was not explicitly included, cross-referencing
targets to frames was done using time stamps. This was possible, but not ideal.
6.4 The Video Offering
The Video offering was designed to generate video clips defined by a temporal range filter. There are two typical uses for this offering. The first is that a tracker can request
segments of video based on detection time ranges. Thus the tracker would not need to download the complete clip, but segments at a time. The second application was for
clients to retrieve video evidence directly without needing to download OM metadata, parse it and then retrieve the video clip using an embedded video link.
In OWS-8, the tracker made use of the video offering, but the presentation of the video data was imperfect and allowances had to be made in software to return the complete
video stream. An ideal software implementation would present the video data accurately synched to frame number and timestamps in the detection data. Additionally, video clips
would be multiplexed with the original VMTI metadata. Video clips were extracted and returned successfully, but no software library was found that would retain the VMTI
metadata.
In addition to direct delivery of video data, the Video Offering presented an OM response that contained a text result that was a URL to the video clip.
In future work, it is worth investigating the application of spatial filters to video observations that have spatial metadata associated with the frame information.
The SOS standard has no provision for direct delivery of binary data as an output format for a GetObservation request. How this would be implemented for observations that have
a time period and not an associated time instant is a matter for discussion outside this document. For VMTI encoded video data, video is also given a spatial component which
opens up the possibility of requesting the video using spatial filters, temporal and spatial filters in combination, using other aspects of the video metadata as filter properties etc. .
One could imagine a query that asks for video data that covers a particular area and time that contains more than 10 detections and has a dominant detection pixel color of white.
Parameters defining the presentation of the returned data such as the CRS of the video frames and mask colors for areas with no data could also be relevant to such a query.
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Copyright © 2012 Open Geospatial Consortium.
6.5 The Frame Image Offering
